Hire the Best Android Developers
in Brazil

I build production-minded automation, mobile apps, APIs, and AI-assisted workflows that need to work reliably outside a demo. My strongest fit is where mobile, Python automation, data capture, and integrations meet: - Python automation: Playwright/Selenium workflows, API integrations, Google Sheets/Excel outputs, scheduled pipelines, data normalization, retries, logging, and handoff documentation. - Mobile/Flutter: 7+ years in mobile, including Flutter/Dart, Android/Kotlin, iOS/Swift, Firebase, offline-first data, API integrations, dynamic forms, image/document capture, push notifications, and release/debug workflows. - AI agents and LLM tooling: practical experience with local automation, agent-style workflows, MCP-style tool integration, structured actions, human approval loops, and debugging tool-calling behavior. - Backend/API work: Django, Google Cloud Functions, REST/GraphQL integrations, Docker environments, BFF patterns, caching, and production troubleshooting. Relevant examples: - Built Python Google Cloud Functions for support/newsletter workflows and Facebook API data caching for a Flutter/Kotlin app. - Built a Django/React allocation system using OR-Tools and automated Google Sheets workflows. - Modernized Flutter apps with dynamic forms, validation, image upload, API compatibility updates, Firebase, and BLoC. - Delivered offline-first Android/Flutter field apps with maps, local databases, sync, scanners, camera/device integrations, and production stability work. - Debugged and improved mobile performance, including large map rendering and app loading/stability issues. I work best on small, urgent, concrete problems: a scraper that must produce clean Excel output, a Flutter/API bug that blocks users, an automation that needs retries/logs, or an agent/local-LLM workflow that is stuck in a loop. I will tell you where the risk is, keep the scope clear, and leave code/documentation that someone else can maintain.

Analytical and detail-oriented Senior Developer with 4+ years of expertise in building high-performance, production-ready mobile ecosystems. Native & Cross-Platform Mastery: Expert in Kotlin (Jetpack Compose, Coroutines) and Flutter (State Management, Flame Engine) to deliver 60fps user experiences. Scalable Architecture: Specialized in clean SDK design, full activity lifecycle management, and robust backend integration using Firebase and Supabase. Modern Tech Stack: Proficient in Retrofit2, RxJava, and Room DB, with a focus on writing clean, maintainable code and concise technical documentation. Client-Centric Solutions: Dedicated to transforming complex business requirements into intuitive mobile products through strategic version control (GIT) and agile collaboration.

12+ years building software for JPMorgan Chase, Cisco, Avaya, and Ford. 12,400+ hours on Upwork alone. AI-augmented engineer running parallel agents with Claude Code and Codex. Production-grade output at a pace that would normally require a team. Built ML-powered palm biometrics kiosk apps for Keyo (Series A, $30M+ raised, thousands of devices deployed, backed by Netflix co-founder), deployed at JPMorgan Chase. Shipped AI-driven identity verification SDKs at Journey.ai (Gartner Cool Vendor, Zero Knowledge Network, multi-modal biometrics with 99.9999% accuracy) used by Cisco Webex and Avaya, and on prototypes for unreleased Ford partnerships. Worked on an AI teaching assistant active in 125+ UK classrooms, 40,000+ questions answered by AI. Led the development of the POV Disposable Camera Android app (3M+ users, 4.9 stars). AI feature integration (OpenAI, Anthropic, Azure), web applications (Next.js, TypeScript), full-stack products with Firebase, Supabase, and Cloud Functions, Kotlin Multiplatform apps, app refactoring and modernization, native Android and AndroidTV apps (Kotlin, Jetpack Compose), IoT and kiosk applications, and video streaming solutions (ExoPlayer, HLS). Software engineer building mobile apps, web apps, and backend systems. Engineering Manager and CTO experience. Delivering multiple times faster than traditional development without sacrificing code quality or architecture. "Excellent development manager. Writes clean code, good eye for design, successfully managing a team of mobile developers. A core manager in our organisation." - Chris Cooper, CEO at NeoMatrix "Takes initiative and drives the product forward, not only through technical skills but understanding the what and the why of what we're building." - Todd Zusman, Director of Engineering at Journey.ai "Strong technical skills, excellent communication, a true team player and great manager. Architect of a complex cross-platform project. We'd happily work with him again." - Cayetana Polanco, CPO at Keyo "A rare find and very dedicated engineer, team lead and manager. Thiago always delivers." - Al Calendario, Director of Integration at Keyo "Accomplished all tasks very well, sometimes beyond expectations. In command of the Android API, managed tasks with little supervision, keen interest in the business purposes of the app." - Stephen Hosking, CEO at NoPowerTXT "Communication is impeccable, incredibly reliable, very detail-oriented. The kind of leader who grows through adversity and never loses sight of the people." - Lynda Yang, SHRM-SCP at Untitled Shows Kotlin, Java, TypeScript, Python Jetpack Compose, MVVM/MVI, Hilt, Room, Retrofit, Coroutines, ExoPlayer Kotlin Multiplatform Firebase (Firestore, Cloud Functions, RTDB), Node.js, Next.js Claude Code, Codex, OpenAI API, Anthropic API, Azure AI GitHub Actions CI/CD, automated code review, multi-worktree workflows PostHog, Crashlytics, Sentry Check the portfolio below and send a message. Happy to discuss your project.

Hi, I'm David. I'm a Software Development student based in Brazil, focused on building modern applications, games, and systems with clean architecture and real-world performance in mind. I combine a developer's mindset with a strong focus on user experience, problem-solving, and practical results. Whether it's coding an application, testing a system, or improving a product, I approach everything thinking like both a developer and an end user. If you need someone who understands not just how to build things, but how they should behave in real scenarios, you're in the right place. Here’s what I bring to your project: Software & Application Development I build applications using modern technologies with a focus on performance, clean code, and scalability. I have experience with mobile and web development, working with tools like Kotlin, Android Studio, and modern development frameworks. Game Development & Systems Design I work with game development (Unity and similar tools), creating systems like inventory, mechanics, and gameplay features. I focus on building structured and scalable systems, not just visuals. Technical QA & Problem Solving I analyze systems to find bugs, inconsistencies, and performance issues. More than just identifying problems, I provide clear explanations and practical solutions that developers can actually implement. My Background: Education: Software Development Student (Brazil) Languages: Native Brazilian Portuguese | Basic English Tools: Git, Android Studio, Unity, VS Code I'm focused on growth, discipline, and delivering real value through my work. Send me a message with a quick overview of your project, and let’s build something solid.

Expert in: Clean Architecture, Clean Code, JavaScript/TypeScript, Python, Java and Rust. I also code well in C/C++, Dart, Kotlin, C#, Bash, Ruby and many more. I am an entrepreneur Senior Software Engineer extremely passionate about engineering software - crafting applications is my profession and hobby. I love solving difficult logic problems, I love finding hidden patterns and I love how programming makes it possible that I can write a letter, a book, a novel (with continuity, cohesion and coherence) into working applications for Windows, Linux, macOS, Android or/and iOS. I have almost a decade of experience in the programming field, it has become a natural part of me already. I've seen it all so far: from well written code bases to the most messy legacy projects. It's possible to summarize my expertise by: I can give life to any - LITERALLY ANY - idea, using clean and easy to update code. Tired of messy code bases and applications struggling under pressure? Say no more and lets schedule a call, because I'm a specialist in converting any of your thoughts and ideas into clean, maintainable, and scalable software solutions. Want to: - Build the next big web thing? Svelte, React or any other. - Take your app to mobile? Flutter, Tauri, Kotlin or any other. - Craft robust APIs? Rust, JavaScript, Python, Java, C/C++ or any other. - Make your life easier with automation? Rust, JavaScript, Python, Java or any other. - Convenience with desktop applications? Tauri, JavaScript, Python, C/C++ or any other. My commitment is to deliver: - Clean and maintainable code. Writing code that is readable, understandable and easy to modify. - Scalable architecture. Designing solutions that can handle increasing complexity, traffic and data loads. - Efficient problem-solving. Applying the best tools and techniques to overcome any technical challenge. - Clear communication. Keeping you informed throughout the development process with regular updates and transparent communication. ❓ How to start? 💬 Write me on Upwork or send the invitation to your job post! I’ll gladly accept your request, offer an intro call to get your idea, requirements, and expectations. 🗝️ Keywords to find me: Software Engineer, Software Architect, Full Stack Developer, Clean Code, Clean Architecture, Web Developer, Mobile Developer, Android Developer, iOS Developer, SaaS Developer, SaaS Engineer, Cloud Developer, Full-Stack Developer, Fullstack Developer, React Developer, Svelte Developer, Node.js Developer, Python Developer, Flutter Developer, API Development, Monolithic Architecture, Microservices Architecture, Cloud Computing (AWS, Azure, GCP), CI/CD, Fintech Software Engineer, Healthcare SaaS Developer, E-commerce Platform Developer, Scalable Applications, User-Friendly Interfaces, Custom SaaS Development, Agile Development, MVP Development, Expert, Senior, Scalability

I am technology enthusiastic and I find always improve my knowledge. I have a great facility to learn the technologies. I communicate well and get always keep the well-being on the development team. I am competent and cumply with deadlines, besides being very proactive. I am constat learning for upgrade my skills.